I noticed a strange sqeeking noise while being max-left or max-right with the steering wheel. It's pretty loud and it's only present when i hold the wheel maximum left or right (if i let it go back just a little, the noise disappears).

After driving a friend's 320d i decided to take mine in for a check, because mine has that strange noise at full steering lock and his doesn't.

The guys at the dealer said they would replace the engine (damper) pulley, the belt and some rollers, all covered by warranty.

My question is - could the engine pulley cause this kind of noise? I insisted they check the power steering pump but they seemed pretty sure they pulley is causing the noise.

Brought the car in last Friday and the dealer replaced the engine vibration damper, the front belt and 2 tensioners, all under warranty.
I was told the sqeeking metallic noise was most likely caused by the vibration damper but they also changed the belt and the tensioners, just in case.

I'm thinking it's your power steering pump. I had a similar problem with an old Toyota celica. I know it's a big difference in cars, but I had similar issues and ended up replacing it. No leaks at all? I did have a small puddle of ps fluid develop under my celica.

Do you full lock your steering wheel a lot?? Maybe I am just old school from my dad but he would rip me a new one when I would full lock my wheel as I was turning. Told me it would screw the pump up doing that. So I go to full lock then back off a little bit. I can hear this noise on mine a little bit but to me I always figured the noise that I was hearing is just the steering pump straining when I am at full lock and trying to cut pressure.

@Hooy - can you please better describe the noise you were hearing from the bad steering pump?

@berserkerx - no, i never hold the steering wheel while at full lock. I just non-intentionally hit full lock while parking the car (not much space for maneuver) and that's when i hear the squeal. I back off the wheel immediately.

The thing is that the noise had completely disappeared for a few months after the dealer replaced the crank vibration damper. Now i don't know if that is the actual problem (and the new one has gone bad also) or it's a combination of that and steering pump/other.

Do you full lock your steering wheel a lot?? Maybe I am just old school from my dad but he would rip me a new one when I would full lock my wheel as I was turning. Told me it would screw the pump up doing that. So I go to full lock then back off a little bit. I can hear this noise on mine a little bit but to me I always figured the noise that I was hearing is just the steering pump straining when I am at full lock and trying to cut pressure.

I agree. It's common knowledge to never bring it to full lock and hold it there. I'm assuming it's because you're forcing the PS pump to work against too high of a resistance and it's straining. Maybe due to this, the belt is slipping on the pulley.

As i said in earlier posts, i have replaced the front belt and all the tensioners (including crank vibration damper) under warranty and the noise returned after no more than 3000km.

Took the car back to BMW and they admitted it's a belt problem (the one that i have is an old model of belt (it was replaced this summer) and it slips on one of the rollers while the load increases - full lock). Talked to a service guy and he mentioned a case in which they replaced the belt 5-6 times on an X3 and the noise kept returning. He said that the last time they did that, BMW had sent a new/improved belt model and that one should work fine.
I will get mine replaced (again) and hopefully they will mount the new belt design and the noise will not return.

Other than the sound discomfort, there is no danger running the car as it is. Post a youtube video if you can, that way i can tell you if it's the same noise as mine.

Cheers,

LE: BMW has replaced (again) the vibration pulley under warranty, but car still does the same noise. They said that for my model there isn't a newer belt part no. so they didn't replace it. They are unable to pinpoint what's causing the noise. I've learned to accept the noise, and avoid doing full locks (still annoying, though)

I just got BMW 320D (2005) from the local dealer and noticed that on full lock there is a clearly audible hissing noise. I read in few sites (not BMW related) that this is normal "pump releasing pressure" BUT then I read that some cars don't have this noise!

I'm just wondering how is your steering now 16 months later??? Do I need to get them to look into it or should I just ignore it?